Researchers at Tufts University in the United States have highlighted that the term low‑carb diet can be imprecise. Yet many scientists describe this dietary pattern as restricting carbohydrate intake to about 30 percent of total daily calories. The findings appear in Critical Reviews in Food Science and Nutrition (CRFSN).
Interest in low‑carb eating has surged in recent times. Even as the diet grows in popularity, there remains ongoing discussion about what daily carbohydrate limits truly qualify as low carb.
To explore this, American researchers reviewed more than 500 studies to understand the characteristics and impacts of low‑carb diets on the body. In the majority of the studies included in the review, a low‑carb diet was defined as either 30 percent of calories from carbohydrates or fewer than 100 grams of carbs per day.
In typical nutrition guidance, carbohydrate intake is set at roughly 50 to 80 percent of total calories, which translates to about 250 to 400 grams per day. That range reflects what many experts consider the baseline needs for an adult.
The researchers emphasized the need for standardized criteria to define low‑carb diets within nutrition science. Having consistent definitions would improve the design and evaluation of public health programs and allow for more precise assessments of any potential benefits of this dietary approach.
Historically, some clinicians have labeled certain weight‑loss diets as among the most risky choices for health. This continuity of concern underscores the importance of clear definitions and careful monitoring when adopting any restrictive eating plan.